The teams take off from the starting line at the Playboy Mansion in Beverly Hills, California and are instructed to fly to Shannon, Ireland. A flight delay leaves teams that thought they were ahead scrambling to catch up. The teams travel to the world's smallest church and then sign up for one of the three ferries departing the next morning. They're then directed to drive 42 miles to Cleggan farm where they must ride a tandem bike to a clue. One member of each team then completes a task that involves more biking -- highwire bicycling while their teammate rides below. Many teams are then frustrated by a task that requires them to fill a basket with fifteen pieces of peat and then transport it using a donkey. Controlling the donkeys proves more difficult for some teams than others and once again some leading teams take a plunge. Ultimately, one team is unable to recover from poor performance on this task and is eliminated from the race.

The remaining ten teams took off from the Pit Stop at the Connemara Heritage Center in Ireland and were instructed to fly to Amsterdam in the Netherlands, nearly 600 miles away and then search the city's canals for a bridge. As the scramble for flights began, all teams secured an initial flight, but others did not make an early connecting flight. Once in the Netherlands, the teams were faced with Detour options involving either heavy lifting or careful searching. Some teams quickly completed their assigned tasks, while others became frustrated and either switched tasks or lost valuable time as they struggled to stick with the task they had chosen. The teams then traveled by bus to their next task, a Roadblock involving ditch vaulting. As the task required the racers to travel across a muddy pit, some found themselves getting very dirty. Afterwards, both team-members were required to ride in a Dutch cargo bike to the Durgerdam Yacht Club, the leg's Pit Stop. Some teams became last on the way, but ultimately one team was unable to overcome having lagged behind throughout the leg and was eliminated from the race.

The remaining nine teams took off from their Pit Stop in a lakeside village in Amsterdam and were instructed to fly Ouagadougou, Burkina Faso in Africa. Upon arrival, the teams took taxis to the area train station, where a long wait for a morning train allowed them to mingle and have fun. The teams then took a train to Bingo in the middle of the African Savannah, where they were faced with a Roadblock. This challenging Roadblock forced one member of each team to deal with camels, a task that proved extremely frustrating for one racer in particular. Upon completing the task, they then led a group of four camels along a marked path. Several teams were forced to backtrack after going in the wrong direction, leading one racer to admit that their partner is better at navigation. Once the teams reached the cluebox at the end of the correct path, they were presented with a Detour. Ultimately, one team that had struggled was able to just make it ahead of another to the Pit Stop on the outskirts of Bingo, causing another team to be eliminated.

The remaining eight teams continued in the fourth leg of the race. Taking off from their Pit Stop in the village of Bingo, they received an offering of a chicken from a local chief and then were instructed to travel 100 miles by taxi Bouda Pelegtanga and find their next clue. Once there, teams were faced with a Detour that tested their skills at either panning for gold or rhythmic dancing. Some teams were slowed by a penalty when their dancing didn't measure up, while others zipped ahead. One team was hit with a new twist in the race requiring them to do additional work. Teams eventually traveled to the Tampouy Goat Market by taxi, where a Roadblock involving a goat proved frustrating for several racers. One team was unable to catch up after having lagged behind the entire race. They arrived at the Pit Stop at the Hotel de Ville and received the unfortunate news that they were eliminated.

The remaining teams take off for the fifth leg of the race from their Pit Stop at the Hotel de Ville and receive a clue instructing them to fly 3,000 miles to Lithuania. All teams end up on flights arriving less than an hour apart and are shuffled thanks to many teams' difficulties in navigating the confusing streets of Lithuania. Teams arrive in marked cars at St. Ann's Church, where a Roadblock requires one team member to make deliveries. Several racers struggle with this task, allowing some teams that found themselves behind to rapidly catch up. Upon completing the task, teams travel to a Lithuanian outdoor ethnographic museum. There, teams search among hundreds of gnomes (Lithuania being the "Land of Gnomes") for a Travelocity Roaming Gnome that must accompany them to the Pit Stop. Teams then choose from Detours that involve either meticulous counting or challenging stilt-walking. In the end, one team is unable to recover from both bad navigation and power struggling and is eliminated from the race.

With five teams eliminated, the teams take off from their Pit Stop at a windmill in Lithuania and receive a clue instructing them to fly to Dubrovnik, Croatia. As the scramble for flights begin, teams try to follow the lead of others, or risk finding their own potentially better option. An error in the tickets received by one team causes them to fall dangerously behind. Upon arriving in Dubrovnik, teams travel to the base of the Fort of St. Lawrence and encounter a Roadblock. The task requires them to help with the restoration of the local architecture. After riding a zip-line, teams are plunged into another task, a Detour. The task allows team to choose between either taking hard physical labor up front, or saving it for the end of the task. One team encounters difficulties with transportation upon completing the task, and is forced to redo part of the leg over after not following the stated instructions in a clue. In the end, however, one team is unable to catch up to another, and is eliminated in a close finish.

The remaining five teams take off from their Pit Stop at the Stone Cross in Dubrovnik, Croatia and receive a clue instructing them to travel by ferry to Ancona, Italy. All teams must first travel by bus to Split, Croatia. All teams make the same ferry, but tricky driving in Ancona causes delays for several teams, such that only two have arrived when the Roadblock opens at 7 A.M. at the Roadblock. One racer struggles repeatedly at the Roadblock, while another team advances their position by opting for a Fast Forward that requires a major physical alteration. Along the way, teams receive a message from home on a Blackberry, which is not allowed to be used for any other purpose. One team is frustrated when they lose their clue. One racer becomes frustrated with their partner during a difficult driving situation, ordering them to "stop this car!" Another team faces a flat-tire, but overcomes the difficulty to avoid last place. The team checking into the Pit Stop at the Boboli Gardens in Florence, Italy is surprised and delighted to learn that they are not eliminated, though less delighted to learn that they will be faced with an additional task on the next leg.

The remaining teams continue in the eighth leg of the race, taking off from their Pit Stop at the Boboli Gardens in Florence, Italy. They receive a clue instructing them to fly 4,000 miles to Mumbai, India and then travel by rickshaw to a newspaper stand, where they must search the Times of India for an advertisement that shows their next destination. Though teams struggle valiantly for airport placement, all placements are neutralized by the newspaper stand's 6 A.M. opening time. After finding the advertisement, teams travel by auto-rickshaw to the Chauhan Tailors where they find themselves faced with a Detour that involves either posting a massive poster or creating a flowery garment. One team also faces an additional task for having come in last in the previous leg. The second of two U-Turns appears and teams find a Roadblock that requires one member of each team to do some heavy hauling. An intense race ensues to the Pit Stop at the Bandra Fort. Ultimately, one team is unable to overcome an earlier strategic blunder and is eliminated from the race.

The remaining four teams take off from their Pit Stop at the Bandra Fort, a nearly 500-year-old fort in Mumbai, India built by the Portuguese, and receive a clue instructing them to fly nearly 4,000 miles to Osaka, Japan. Once in Japan, teams travel to Kishiwata Castle by taxi, where they find another clue instructing them travel by taxi to Noda Station and locate a cleaning man who has their next clue. The clue gives details for a Roadblock task that requires one member of each team to become a taxi driver and do a taxing taxi drive through the streets of Osaka. Upon completing the task, racers return to their partners with the clue, which instructs them to travel to the sixteenth century Buddhist Kita-Mido Temple. The next task they face is a Detour requiring them to either sniff out flowers or take part in a robotic soccer match. In the end, one team makes a critical mistake in boarding a flight that arrives over three hours after the other teams' flight. They arrive in Osaka, complete the tasks, and receive surprising but pleasant news upon arriving at the leg's Pit Stop, Tempozan Park.

The remaining teams continue in the penultimate leg of the race, with the guarantee that one team will be eliminated and the first three at the Pit Stop will be the final three racing for one million dollars. They take off from their Pit Stop in Osaka, Japan and receive a clue instructing them to travel to the Floating Garden of the Umeda Sky Garden. Its 10 A.M. opening time gives the lowest ranked team a great advantage and, upon arriving there, teams receive a clue instructing them to fly 1,000 miles to Taipei, Taiwan. Once in Taiwan, teams travel by high-speed rail to Taichung and then taxi to Acrobatics Jeep. One team, becoming increasingly infuriated by the placement of another, declares themselves to be "out for blood" and threatens to "rip the dreads" out of another racer's head. Teams face a Roadblock that requires one member of each team to undergo two harrowing rides in stunt cars. They next take another high-speed rail trip, but one must complete a Speed Bump before continuing. All teams complete the Detour, in which they walk barefoot on jagged stone. They race for the Pit Stop at Chiang Kai-Shek Memorial Hall Plaza, a monument to the late president of China. One team arrives last and receives the news that they have not reached the final three and are eliminated from the race.

Ronald Hsu & Christina Hsu, TK Erwin & Rachel Rosales and Nicolas Fulks & Donald Jerousek are the three teams racing for the top prize of one million dollars. They take off from their Pit Stop at the Chiang Kai-Shek Memorial Hall Plaza in Taipei, Taiwan and receive a clue instructing them to immediately fly to the final destination city of Anchorage, Alaska, over 4,500 miles away. As teams scramble for flights, all obtain the same flight, but one manages a valuable upgrade. Once in Alaska, teams travel to 6th Avenue Outfitters, an adventure store, to pick up vital gear for tasks and a clue. One team, however, neglects to pick up their gear and does not realize their mistake until reaching the Detour. This particular Detour, at the Ship Creek Boat Launch, requires teams to choose between tasks involving either cod or crabs. The teams then taxi sixty miles to the Twenty Mile River and then take a high-speed boat ride to the Twenty Mile Glacier, which they scale. Next, teams take a thrilling taxi ride across the Alaskan wilderness to Merrill Field and taxi to Goose Lake Park. There, they face the final Roadblock, in which one member of each team is required to complete a task that involves the placement of various objects featured throughout the race. Teams then receive two clues instructing them to travel to statues, and then finally are instructed to travel to the Girdwood Airport and run to the finish line. In a near-photo finish, one team just ekes out another to win The Amazing Race 12 and claim the one million dollar prize.